What shapes black hole accretion?

Accreting black holes can produce luminous disks, hot X-ray coronae, powerful jets, and winds. What determines which of these components emerge, how they evolve, and how they share the available energy? The answer depends on how microscopic plasma processes interact with the evolving structure of the accretion flow.

Recent X-ray spectroscopy and polarization measurements, coordinated multiwavelength observations, and evidence for neutrino emission are testing the limits of standard accretion models. Interpreting these signals requires understanding how plasma moves between physical regimes, from dense regions where collisions keep electrons and protons near a common temperature to dilute regions where their temperatures diverge and particles are accelerated to high energies. I investigate how these processes interact with evolving magnetic fields to explain when coronae and jets emerge, how black holes transfer energy to their surroundings, and how reliably their emission reveals black hole spin.